neem oil works great as a way to prevent insect attacks. Diatomaceous earth works really good too. Be careful not to over water, since that can attract bugs too. And yes they do look a little pale, get a better soil and transplant to a bigger container.
Hello @Huicho ! What you mean worms? If you mean earthworms then you don't have to worry about them. Earth worms are beneficial. They decompose organic matter so the nutrients can be available for the plants. If you mean caterpillars, larva's of lepidoptera species and liriomyza then you need to spray with bacillus thuringiensis var. kurstaki and its also a wise move to spray even if you don't have a problem as a precaution measure. The yellowing is nitrogen deficiency that comes from root bound. You need to transplant it and it is crucial to do it at least one week before it goes to flowering stage. Transplant it in a pot 3-4 times bigger than the current one. Happy growing ! :facepunch: